package com.sky.service.impl;

import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.List;

@Service
public class ShoppingCartServiceImpl implements ShoppingCartService {

    @Autowired
    private ShoppingCartMapper shoppingCartMapper;

    @Autowired
    private DishMapper dishMapper;

    @Autowired
    private SetmealMapper setmealMapper;

    /**
     * 添加购物车
     *
     * @param shoppingCartDTO
     */
    public void addShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        //判断添加到购物车中的商品是否已经存在了
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO, shoppingCart);
        Long userId = BaseContext.getCurrentId();//从threadLocal中获取当前用户的id
        shoppingCart.setUserId(userId);

        //查询购物车，判断本次要添加的商品是否已经存在
        List<ShoppingCart> shoppingCartList = shoppingCartMapper.list(shoppingCart);

        //如果存在了，就将该商品的数量 + 1
        if (shoppingCartList != null && shoppingCartList.size() > 0) {
            //理论上我们查询的集合中只有一条符合要求的数据，所有get(0)就是我们添加到购物车中的商品
            ShoppingCart cart = shoppingCartList.get(0);
            cart.setNumber(cart.getNumber() + 1);
            shoppingCartMapper.updateNumberById(cart);
        } else {//如果不存在，就插入一条数据
            //判断本次添加进购物车的是菜品还是套餐
            Long dishId = shoppingCartDTO.getDishId();
            if (dishId != null) {//说明是菜品
                Dish dish = dishMapper.getById(dishId);//根据id查询出添加菜品的具体信息
                shoppingCart.setName(dish.getName());
                shoppingCart.setAmount(dish.getPrice());
                shoppingCart.setImage(dish.getImage());
            } else {//否则就是套餐
                Setmeal setmeal = setmealMapper.getById(shoppingCartDTO.getSetmealId());
                shoppingCart.setName(setmeal.getName());
                shoppingCart.setImage(setmeal.getImage());
                shoppingCart.setAmount(setmeal.getPrice());
            }
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartMapper.insert(shoppingCart);
        }
    }

    /**
     * 查询购物车
     *
     * @return
     */
    public List<ShoppingCart> showShoppingCart() {
        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = new ShoppingCart();
        shoppingCart.setUserId(userId);
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        return list;
    }

    /**
     * 清空购物车
     */
    public void cleanShoppingCart() {
        Long userId = BaseContext.getCurrentId();
        shoppingCartMapper.deleteByUserId(userId);
    }

    /**
     * 删除购物车当中的一个商品
     *
     * @param shoppingCartDTO
     */
    public void subShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        //将shoppingCartDTO中的值复制给shoppingCart对象
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO, shoppingCart);
        //设置查询条件，查询当前登录用户的购物车数据
        shoppingCart.setUserId(BaseContext.getCurrentId());

        List<ShoppingCart> list = shoppingCartMapper.selectByCard(shoppingCart);

        if (list != null && list.size() > 0) {
            //理论来说，只会有一个结果满足购物车的条件查询
            shoppingCart = list.get(0);

            Integer number = shoppingCart.getNumber();
            if (number == 1) {
                //当前商品在购物车中的份数为1，直接删除当前记录
                shoppingCartMapper.deleteById(shoppingCart.getId());
            } else {
                //当前商品在购物车中的份数不为1，修改份数即可
                shoppingCart.setNumber(shoppingCart.getNumber() - 1);
                shoppingCartMapper.update(shoppingCart);
            }
        }
    }
}
